Assessing Officer jurisdiction based on assigned area; higher authorities determine boundary disputes and pre-assessment challenges promptly. Jurisdiction is vested in an Assessing Officer by directions under section 120; within the vested area the officer has jurisdiction over business or profession where the place or principal place of business is situated in the area and over residents. Disputes about jurisdiction are determined by the designated senior officers or, if they disagree, by the Board or a Board specified senior officer. An assessee's right to question jurisdiction is limited by filing returns or expiry of times allowed by statutory notices; where jurisdiction is contested before assessment the Assessing Officer must refer the matter for determination. Every Assessing Officer vested with an area has all statutory powers over income within that area.